Stockholders' Equity (Tables)

12 Months Ended

Sep. 30, 2015

Dividends Declared and Paid

	Year Ended September 30,
	2015		2014		2013
Dividends declared and paid	$	24,646	$	21,263	$	21,866
Dividend per share amount		0.38		0.32		0.32

Stock-based Compensation Expense Recognized

	Year Ended September 30,
	2015		2014		2013
Employee stock-based compensation expense	$	14,255	$	11,241	$	9,414

Stock Options [Member]

Schedule of Assumptions Used in Estimate of Fair Value of Stock Option Awards

	Year Ended September 30,
	2015				2014			2013
Expected term (years)		6.2	-	8.8	5.8	-	8.6	5.8	-	8.6
Estimated volatility		36.5%			38.5%			48.7%	-	54.9%
Estimated dividend yield		0.7%			0.8%			0.8%	-	1.0%
Risk-free interest rate		2.0%	-	2.3%	1.7%	-	2.5%	0.8%	-	1.3%

Weighted Average Grant Date Fair Value of Options Granted

	Year Ended September 30,
	2015		2014		2013
Weighted-average grant date fair value of options	$	17.02	$	15.63	$	15.84

Activity for Stock Option Awards

	Number		Weighted-Average Exercise Price
Balance at September 30, 2014		4,501	$	28.08
Options granted		751		46.55
Options exercised		(568)		17.48
Options forfeited		(43)		38.24
Balance at September 30, 2015		4,641		32.28

Changes in Nonvested Stock Options

	Number		Weighted-Average Exercise Price
Balance at September 30, 2014		1,679	$	34.83
Options granted		751		46.55
Options vested		(664)		33.07
Options forfeited		(42)		38.24
Balance at September 30, 2015		1,724		40.54

Stock Options Vested, Or Expected to Vest and Are Exercisable

	Number		Weighted- Average Exercise Price		Weighted- Average Remaining Life in Years		Aggregate Intrinsic Value
Options outstanding		4,641	$	32.28		5.7	$	43,646
Options vested and exercisable		2,917		27.40		4.3		38,880
Options vested and expected to vest		4,564		32.08		5.6		43,595

Other Stock Option Information

	Year Ended September 30,
	2015		2014		2013
Total fair value of stock options vested	$	9,656	$	9,459	$	7,271
Total intrinsic value of options exercised		18,876		14,549		19,692
Cash received from exercises of stock options		8,400		9,772		8,272
Excess tax benefit realized from exercise of stock options		6,959		3,751		5,154

Restricted Stock Award [Member]

Activity for Stock Option Awards

	Number		Fair Value per Share
Balance at September 30, 2014		24	$	39.43
Shares granted		-		n/a
Shares vested		-		n/a
Shares forfeited		-		n/a
Balance at September 30, 2015		24		39.43